initial version

Frameworks/MQTTnet.NetStandard/Implementations/MqttCommunicationAdapterFactory.cs

@@ -1,30 +0,0 @@
-using System;
-using MQTTnet.Core.Adapter;
-using MQTTnet.Core.Client;
-using MQTTnet.Core.Diagnostics;
-using MQTTnet.Core.Serializer;
-
-namespace MQTTnet.Implementations
-{
-    public class MqttCommunicationAdapterFactory : IMqttCommunicationAdapterFactory
-    {
-        public IMqttCommunicationAdapter CreateMqttCommunicationAdapter(IMqttClientOptions options)
-        {
-            if (options == null) throw new ArgumentNullException(nameof(options));
-
-            if (options is MqttClientTcpOptions tcpOptions)
-            {
-                var trace = new MqttNetTrace();
-                return new MqttChannelCommunicationAdapter(new MqttTcpChannel(tcpOptions), new MqttPacketSerializer { ProtocolVersion = options.ProtocolVersion }, trace);
-            }
-
-            if (options is MqttClientWebSocketOptions webSocketOptions)
-            {
-                var trace = new MqttNetTrace();
-                return new MqttChannelCommunicationAdapter(new MqttWebSocketChannel(webSocketOptions), new MqttPacketSerializer { ProtocolVersion = options.ProtocolVersion }, trace);
-            }
-
-            throw new NotSupportedException();
-        }
-    }
-}

Frameworks/MQTTnet.NetStandard/Implementations/MqttServerAdapter.cs

@@ -7,23 +7,26 @@ using System.Security.Cryptography.X509Certificates;
 using System.Threading;
 using System.Threading.Tasks;
 using MQTTnet.Core.Adapter;
-using MQTTnet.Core.Diagnostics;
 using MQTTnet.Core.Serializer;
 using MQTTnet.Core.Server;
+using Microsoft.Extensions.Logging;
+using MQTTnet.Core.Client;
 
 namespace MQTTnet.Implementations
 {
     public class MqttServerAdapter : IMqttServerAdapter, IDisposable
     {
-        private readonly MqttNetTrace _trace;
+        private readonly ILogger<MqttServerAdapter> _logger;
+        private readonly IMqttCommunicationAdapterFactory _mqttCommunicationAdapterFactory;
         private CancellationTokenSource _cancellationTokenSource;
         private Socket _defaultEndpointSocket;
         private Socket _tlsEndpointSocket;
         private X509Certificate2 _tlsCertificate;
 
-        public MqttServerAdapter(MqttNetTrace trace)
+        public MqttServerAdapter(ILogger<MqttServerAdapter> logger, IMqttCommunicationAdapterFactory mqttCommunicationAdapterFactory)
         {
-            _trace = trace ?? throw new ArgumentNullException(nameof(trace));
+            _logger = logger ?? throw new ArgumentNullException(nameof(logger));
+            _mqttCommunicationAdapterFactory = mqttCommunicationAdapterFactory ?? throw new ArgumentNullException(nameof(mqttCommunicationAdapterFactory));
         }
 
         public event EventHandler<MqttServerAdapterClientAcceptedEventArgs> ClientAccepted;
@@ -95,17 +98,17 @@ namespace MQTTnet.Implementations
                 try
                 {
                     //todo: else branch can be used with min dependency NET46
-#if NET45
+#if NET451
                     var clientSocket = await Task.Factory.FromAsync(_defaultEndpointSocket.BeginAccept, _defaultEndpointSocket.EndAccept, null).ConfigureAwait(false);
 #else
                     var clientSocket = await _defaultEndpointSocket.AcceptAsync().ConfigureAwait(false);
 #endif
-                    var clientAdapter = new MqttChannelCommunicationAdapter(new MqttTcpChannel(clientSocket, null), new MqttPacketSerializer(), _trace);
+                    var clientAdapter = _mqttCommunicationAdapterFactory.CreateServerMqttCommunicationAdapter(new MqttTcpChannel(clientSocket, null));
                     ClientAccepted?.Invoke(this, new MqttServerAdapterClientAcceptedEventArgs(clientAdapter));
                 }
                 catch (Exception exception)
                 {
-                    _trace.Error(nameof(MqttServerAdapter), exception, "Error while accepting connection at default endpoint.");
+                    _logger.LogError(new EventId(), exception, "Error while accepting connection at default endpoint.");
 
                     //excessive CPU consumed if in endless loop of socket errors
                     await Task.Delay(TimeSpan.FromSeconds(1), cancellationToken).ConfigureAwait(false);
@@ -119,7 +122,7 @@ namespace MQTTnet.Implementations
             {
                 try
                 {
-#if NET45
+#if NET451
                     var clientSocket = await Task.Factory.FromAsync(_tlsEndpointSocket.BeginAccept, _tlsEndpointSocket.EndAccept, null).ConfigureAwait(false);
 #else
                     var clientSocket = await _tlsEndpointSocket.AcceptAsync().ConfigureAwait(false);
@@ -128,12 +131,12 @@ namespace MQTTnet.Implementations
                     var sslStream = new SslStream(new NetworkStream(clientSocket));
                     await sslStream.AuthenticateAsServerAsync(_tlsCertificate, false, SslProtocols.Tls12, false).ConfigureAwait(false);
 
-                    var clientAdapter = new MqttChannelCommunicationAdapter(new MqttTcpChannel(clientSocket, sslStream), new MqttPacketSerializer(), _trace);
+                    var clientAdapter = _mqttCommunicationAdapterFactory.CreateServerMqttCommunicationAdapter(new MqttTcpChannel(clientSocket, sslStream));
                     ClientAccepted?.Invoke(this, new MqttServerAdapterClientAcceptedEventArgs(clientAdapter));
                 }
                 catch (Exception exception)
                 {
-                    _trace.Error(nameof(MqttServerAdapter), exception, "Error while accepting connection at TLS endpoint.");
+                    _logger.LogError(new EventId(), exception, "Error while accepting connection at TLS endpoint.");
 
                     //excessive CPU consumed if in endless loop of socket errors
                     await Task.Delay(TimeSpan.FromSeconds(1), cancellationToken).ConfigureAwait(false);

Frameworks/MQTTnet.NetStandard/Implementations/MqttTcpChannel.cs

@@ -59,7 +59,7 @@ namespace MQTTnet.Implementations
             }
 
 //todo: else brach can be used with min dependency NET46
-#if NET45
+#if NET451
             await Task.Factory.FromAsync(_socket.BeginConnect, _socket.EndConnect, _options.Server, _options.GetPort(), null).ConfigureAwait(false);
 #else
             await _socket.ConnectAsync(_options.Server, _options.GetPort()).ConfigureAwait(false);

Frameworks/MQTTnet.NetStandard/MQTTnet.Netstandard.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>netstandard1.3;net45</TargetFrameworks>
+    <TargetFrameworks>netstandard1.3;net451</TargetFrameworks>
     <AssemblyName>MQTTnet</AssemblyName>
     <RootNamespace>MQTTnet</RootNamespace>
     <AssemblyVersion>2.5.0.0</AssemblyVersion>
@@ -18,6 +18,11 @@
 
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'" />
 
+  <ItemGroup>
+    <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="1.1.1" />
+    <PackageReference Include="Microsoft.Extensions.Logging" Version="1.1.2" />
+  </ItemGroup>
+
   <ItemGroup>
     <ProjectReference Include="..\..\MQTTnet.Core\MQTTnet.Core.csproj" />
   </ItemGroup>

Frameworks/MQTTnet.NetStandard/MqttClientFactory.cs

@@ -1,20 +0,0 @@
-using MQTTnet.Core.Client;
-using MQTTnet.Core.Diagnostics;
-using MQTTnet.Core.ManagedClient;
-using MQTTnet.Implementations;
-
-namespace MQTTnet
-{
-    public class MqttClientFactory : IMqttClientFactory
-    {
-        public IMqttClient CreateMqttClient(IMqttNetTraceHandler traceHandler = null)
-        {
-            return new MqttClient(new MqttCommunicationAdapterFactory(), new MqttNetTrace(traceHandler));
-        }
-
-        public ManagedMqttClient CreateManagedMqttClient(IMqttNetTraceHandler traceHandler = null)
-        {
-            return new ManagedMqttClient(new MqttCommunicationAdapterFactory(), new MqttNetTrace());
-        }
-    }
-}

Frameworks/MQTTnet.NetStandard/MqttFactory.cs

@@ -0,0 +1,104 @@
+using System;
+using MQTTnet.Core.Adapter;
+using MQTTnet.Core.Client;
+using MQTTnet.Core.Serializer;
+using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.DependencyInjection;
+using MQTTnet.Implementations;
+using MQTTnet.Core.ManagedClient;
+using MQTTnet.Core.Server;
+using System.Linq;
+using MQTTnet.Core.Channel;
+
+namespace MQTTnet
+{
+    public class MqttFactory : IMqttCommunicationAdapterFactory, IMqttClientSesssionFactory, IMqttClientFactory, IMqttServerFactory
+    {
+        private readonly IServiceProvider _serviceProvider;
+
+        private static IServiceProvider BuildServiceProvider()
+        {
+            return new ServiceCollection()
+                .AddMqttClient()
+                .AddMqttServer()
+                .AddLogging()
+                .BuildServiceProvider();
+        }
+
+        public MqttFactory()
+            : this(BuildServiceProvider())
+        {
+        }
+
+        public MqttFactory(IServiceProvider serviceProvider)
+        {
+            _serviceProvider = serviceProvider;
+        }
+
+        public IMqttCommunicationAdapter CreateClientMqttCommunicationAdapter(IMqttClientOptions options)
+        {
+            var logger = _serviceProvider.GetRequiredService<ILogger<MqttChannelCommunicationAdapter>>();
+            return new MqttChannelCommunicationAdapter(CreateMqttCommunicationChannel(options), CreateSerializer(options.ProtocolVersion), logger);
+        }
+
+        public IMqttCommunicationAdapter CreateServerMqttCommunicationAdapter(IMqttCommunicationChannel channel)
+        {
+            var serializer = _serviceProvider.GetRequiredService<IMqttPacketSerializer>();
+            var logger = _serviceProvider.GetRequiredService<ILogger<MqttChannelCommunicationAdapter>>();
+            return new MqttChannelCommunicationAdapter(channel, serializer, logger);
+        }
+
+        public IMqttCommunicationChannel CreateMqttCommunicationChannel(IMqttClientOptions options)
+        {
+            if (options == null) throw new ArgumentNullException(nameof(options));
+
+            switch (options)
+            {
+                case MqttClientTcpOptions tcpOptions:
+                    return CreateTcpChannel(tcpOptions);
+                case MqttClientWebSocketOptions webSocketOptions:
+                    return CreateWebSocketChannel(webSocketOptions);
+                default:
+                    throw new NotSupportedException();
+            }
+        }        
+
+        public MqttTcpChannel CreateTcpChannel(MqttClientTcpOptions tcpOptions)
+        {
+            return new MqttTcpChannel(tcpOptions);
+        }
+
+        public MqttWebSocketChannel CreateWebSocketChannel(MqttClientWebSocketOptions webSocketOptions)
+        {
+            return new MqttWebSocketChannel(webSocketOptions);
+        }
+
+        public MqttPacketSerializer CreateSerializer(MqttProtocolVersion protocolVersion)
+        {
+            return new MqttPacketSerializer()
+            {
+                ProtocolVersion = protocolVersion
+            };
+        }
+
+        public MqttClientSession CreateClientSession(string sessionId, MqttClientSessionsManager mqttClientSessionsManager)
+        {
+            return new MqttClientSession(sessionId, mqttClientSessionsManager, _serviceProvider.GetRequiredService<ILogger<MqttClientSession>>(), _serviceProvider.GetRequiredService<ILogger<MqttClientPendingMessagesQueue>>());
+        }
+
+        public IMqttClient CreateMqttClient()
+        {
+            return _serviceProvider.GetRequiredService<IMqttClient>();
+        }
+
+        public ManagedMqttClient CreateManagedMqttClient()
+        {
+            return _serviceProvider.GetRequiredService<ManagedMqttClient>();
+        }
+
+        public IMqttServer CreateMqttServer()
+        {
+            return _serviceProvider.GetRequiredService<IMqttServer>();
+        }
+    }
+}

Frameworks/MQTTnet.NetStandard/MqttServerFactory.cs

@@ -1,20 +0,0 @@
-using System;
-using System.Collections.Generic;
-using MQTTnet.Core.Adapter;
-using MQTTnet.Core.Diagnostics;
-using MQTTnet.Core.Server;
-using MQTTnet.Implementations;
-
-namespace MQTTnet
-{
-    public class MqttServerFactory : IMqttServerFactory
-    {
-        public IMqttServer CreateMqttServer(MqttServerOptions options, IMqttNetTraceHandler traceHandler = null)
-        {
-            if (options == null) throw new ArgumentNullException(nameof(options));
-
-            var trace = new MqttNetTrace(traceHandler);
-            return new MqttServer(options, new List<IMqttServerAdapter> { new MqttServerAdapter(trace) }, trace);
-        }
-    }
-}

Frameworks/MQTTnet.NetStandard/ServiceCollectionExtensions.cs

@@ -0,0 +1,55 @@
+using Microsoft.Extensions.DependencyInjection;
+using MQTTnet.Core.Adapter;
+using MQTTnet.Core.Client;
+using MQTTnet.Core.ManagedClient;
+using MQTTnet.Core.Serializer;
+using MQTTnet.Core.Server;
+using MQTTnet.Implementations;
+using System;
+
+namespace MQTTnet
+{
+    public static class ServiceCollectionExtensions
+    {
+        public static IServiceCollection AddMqttServer(this IServiceCollection services)
+        {
+            services.AddOptions();
+            services.AddSingleton<MqttFactory>();
+            services.AddSingleton<IMqttCommunicationAdapterFactory, MqttFactory>();
+            services.AddSingleton<IMqttClientSesssionFactory, MqttFactory>();
+
+
+            services.AddSingleton<IMqttServer,MqttServer>();
+            services.AddSingleton<MqttServer>();
+
+            services.AddTransient<IMqttServerAdapter, MqttServerAdapter>();
+            services.AddTransient<IMqttPacketSerializer, MqttPacketSerializer>();
+
+            services.AddTransient<MqttClientSessionsManager>();
+            services.AddTransient<MqttClientRetainedMessagesManager>();
+
+            return services;
+        }
+
+        public static IServiceCollection AddMqttServer(this IServiceCollection services, Action<MqttServerOptions> configureOptions)
+        {
+            return services
+                .AddMqttServer()
+                .Configure(configureOptions);
+        }
+
+        public static IServiceCollection AddMqttClient(this IServiceCollection services)
+        {
+            services.AddSingleton<MqttFactory>();
+            services.AddSingleton<IMqttCommunicationAdapterFactory, MqttFactory>();
+
+            services.AddTransient<IMqttClient, MqttClient>();
+            services.AddTransient<MqttClient>();
+            services.AddTransient<IMqttPacketSerializer, MqttPacketSerializer>();
+            services.AddTransient<ManagedMqttClient>();
+            services.AddTransient<MqttPacketDispatcher>();
+
+            return services;
+        }
+    }
+}

MQTTnet.Core/Adapter/IMqttCommunicationAdapterFactory.cs

@@ -0,0 +1,12 @@
+using MQTTnet.Core.Client;
+using MQTTnet.Core.Channel;
+
+namespace MQTTnet.Core.Adapter
+{
+    public interface IMqttCommunicationAdapterFactory
+    {
+        IMqttCommunicationAdapter CreateClientMqttCommunicationAdapter(IMqttClientOptions options);
+
+        IMqttCommunicationAdapter CreateServerMqttCommunicationAdapter(IMqttCommunicationChannel channel);
+    }
+}

MQTTnet.Core/Adapter/MqttChannelCommunicationAdapter.cs

@@ -4,23 +4,23 @@ using System.IO;
 using System.Threading;
 using System.Threading.Tasks;
 using MQTTnet.Core.Channel;
-using MQTTnet.Core.Diagnostics;
 using MQTTnet.Core.Exceptions;
 using MQTTnet.Core.Internal;
 using MQTTnet.Core.Packets;
 using MQTTnet.Core.Serializer;
+using Microsoft.Extensions.Logging;
 
 namespace MQTTnet.Core.Adapter
 {
     public class MqttChannelCommunicationAdapter : IMqttCommunicationAdapter
     {
-        private readonly MqttNetTrace _trace;
+        private readonly ILogger<MqttChannelCommunicationAdapter> _logger;
         private readonly IMqttCommunicationChannel _channel;
         private readonly SemaphoreSlim _semaphore = new SemaphoreSlim(1, 1);
 
-        public MqttChannelCommunicationAdapter(IMqttCommunicationChannel channel, IMqttPacketSerializer serializer, MqttNetTrace trace)
+        public MqttChannelCommunicationAdapter(IMqttCommunicationChannel channel, IMqttPacketSerializer serializer, ILogger<MqttChannelCommunicationAdapter> logger)
         {
-            _trace = trace ?? throw new ArgumentNullException(nameof(trace));
+            _logger = logger ?? throw new ArgumentNullException(nameof(logger));
             _channel = channel ?? throw new ArgumentNullException(nameof(channel));
             PacketSerializer = serializer ?? throw new ArgumentNullException(nameof(serializer));
         }
@@ -96,7 +96,7 @@ namespace MQTTnet.Core.Adapter
                         continue;
                     }
 
-                    _trace.Information(nameof(MqttChannelCommunicationAdapter), "TX >>> {0} [Timeout={1}]", packet, timeout);
+                    _logger.LogInformation("TX >>> {0} [Timeout={1}]", packet, timeout);
 
                     var writeBuffer = PacketSerializer.Serialize(packet);
                     await _channel.SendStream.WriteAsync(writeBuffer, 0, writeBuffer.Length, cancellationToken).ConfigureAwait(false);
@@ -162,7 +162,7 @@ namespace MQTTnet.Core.Adapter
                     throw new MqttProtocolViolationException("Received malformed packet.");
                 }
 
-                _trace.Information(nameof(MqttChannelCommunicationAdapter), "RX <<< {0}", packet);
+                _logger.LogInformation("RX <<< {0}", packet);
                 return packet;
             }
             catch (TaskCanceledException)

MQTTnet.Core/Client/IMqttClientFactory.cs

@@ -1,12 +1,11 @@
-using MQTTnet.Core.Diagnostics;
-using MQTTnet.Core.ManagedClient;
+using MQTTnet.Core.ManagedClient;
 
 namespace MQTTnet.Core.Client
 {
     public interface IMqttClientFactory
     {
-        IMqttClient CreateMqttClient(IMqttNetTraceHandler traceHandler = null);
+        IMqttClient CreateMqttClient();
 
-        ManagedMqttClient CreateManagedMqttClient(IMqttNetTraceHandler traceHandler = null);
+        ManagedMqttClient CreateManagedMqttClient();
     }
 }

MQTTnet.Core/Client/IMqttCommunicationAdapterFactory.cs

@@ -1,9 +0,0 @@
-using MQTTnet.Core.Adapter;
-
-namespace MQTTnet.Core.Client
-{
-    public interface IMqttCommunicationAdapterFactory
-    {
-        IMqttCommunicationAdapter CreateMqttCommunicationAdapter(IMqttClientOptions options);
-    }
-}

MQTTnet.Core/Client/MqttClient.cs

@@ -4,11 +4,11 @@ using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
 using MQTTnet.Core.Adapter;
-using MQTTnet.Core.Diagnostics;
 using MQTTnet.Core.Exceptions;
 using MQTTnet.Core.Internal;
 using MQTTnet.Core.Packets;
 using MQTTnet.Core.Protocol;
+using Microsoft.Extensions.Logging;
 
 namespace MQTTnet.Core.Client
 {
@@ -16,21 +16,21 @@ namespace MQTTnet.Core.Client
     {
         private readonly HashSet<ushort> _unacknowledgedPublishPackets = new HashSet<ushort>();
         private readonly MqttPacketDispatcher _packetDispatcher;
-        private readonly IMqttCommunicationAdapterFactory _communicationChannelFactory;
-        private readonly MqttNetTrace _trace;
+        private readonly IMqttCommunicationAdapterFactory _communicationAdapterFactory;
+        private readonly ILogger<MqttClient> _logger;
 
         private IMqttClientOptions _options;
         private bool _isReceivingPackets;
         private int _latestPacketIdentifier;
         private CancellationTokenSource _cancellationTokenSource;
         private IMqttCommunicationAdapter _adapter;
+        private IDisposable _scopeHandle;
 
-        public MqttClient(IMqttCommunicationAdapterFactory communicationChannelFactory, MqttNetTrace trace)
+        public MqttClient(IMqttCommunicationAdapterFactory communicationAdapterFactory, ILogger<MqttClient> logger, MqttPacketDispatcher packetDispatcher)
         {
-            _trace = trace ?? throw new ArgumentNullException(nameof(trace));
-            _communicationChannelFactory = communicationChannelFactory ?? throw new ArgumentNullException(nameof(communicationChannelFactory));
-
-            _packetDispatcher = new MqttPacketDispatcher(trace);
+            _communicationAdapterFactory = communicationAdapterFactory ?? throw new ArgumentNullException(nameof(communicationAdapterFactory));
+            _logger = logger ?? throw new ArgumentNullException(nameof(logger));
+            _packetDispatcher = packetDispatcher ?? throw new ArgumentNullException(nameof(packetDispatcher));
         }
 
         public event EventHandler<MqttClientConnectedEventArgs> Connected;
@@ -52,16 +52,17 @@ namespace MQTTnet.Core.Client
                 _latestPacketIdentifier = 0;
                 _packetDispatcher.Reset();
 
-                _adapter = _communicationChannelFactory.CreateMqttCommunicationAdapter(options);
+                _adapter = _communicationAdapterFactory.CreateClientMqttCommunicationAdapter(options);
 
-                _trace.Verbose(nameof(MqttClient), "Trying to connect with server.");
+                _scopeHandle = _logger.BeginScope(options.ClientId);
+                _logger.LogTrace("Trying to connect with server.");
                 await _adapter.ConnectAsync(_options.DefaultCommunicationTimeout).ConfigureAwait(false);
-                _trace.Verbose(nameof(MqttClient), "Connection with server established.");
+                _logger.LogTrace("Connection with server established.");
 
                 await SetupIncomingPacketProcessingAsync();
                 var connectResponse = await AuthenticateAsync(options.WillMessage);
 
-                _trace.Verbose(nameof(MqttClient), "MQTT connection with server established.");
+                _logger.LogTrace("MQTT connection with server established.");
 
                 if (_options.KeepAlivePeriod != TimeSpan.Zero)
                 {
@@ -93,6 +94,7 @@ namespace MQTTnet.Core.Client
             finally
             {
                 await DisconnectInternalAsync().ConfigureAwait(false);
+                _scopeHandle.Dispose();
             }
         }
 
@@ -246,11 +248,11 @@ namespace MQTTnet.Core.Client
             try
             {
                 await _adapter.DisconnectAsync(_options.DefaultCommunicationTimeout).ConfigureAwait(false);
-                _trace.Information(nameof(MqttClient), "Disconnected from adapter.");
+                _logger.LogInformation("Disconnected from adapter.");
             }
             catch (Exception exception)
             {
-                _trace.Warning(nameof(MqttClient), exception, "Error while disconnecting from adapter.");
+                _logger.LogWarning(new EventId(), exception, "Error while disconnecting from adapter.");
             }
             finally
             {
@@ -262,7 +264,7 @@ namespace MQTTnet.Core.Client
         {
             try
             {
-                _trace.Information(nameof(MqttClient), "Received <<< {0}", packet);
+                _logger.LogInformation("Received <<< {0}", packet);
 
                 if (packet is MqttPingReqPacket)
                 {
@@ -292,7 +294,7 @@ namespace MQTTnet.Core.Client
             }
             catch (Exception exception)
             {
-                _trace.Error(nameof(MqttClient), exception, "Unhandled exception while processing received packet.");
+                _logger.LogError(new EventId(), exception, "Unhandled exception while processing received packet.");
             }
         }
 
@@ -305,7 +307,7 @@ namespace MQTTnet.Core.Client
             }
             catch (Exception exception)
             {
-                _trace.Error(nameof(MqttClient), exception, "Unhandled exception while handling application message.");
+                _logger.LogError(new EventId(), exception, "Unhandled exception while handling application message.");
             }
         }
 
@@ -369,7 +371,7 @@ namespace MQTTnet.Core.Client
 
         private async Task SendKeepAliveMessagesAsync(CancellationToken cancellationToken)
         {
-            _trace.Information(nameof(MqttClient), "Start sending keep alive packets.");
+            _logger.LogInformation("Start sending keep alive packets.");
 
             try
             {
@@ -394,23 +396,23 @@ namespace MQTTnet.Core.Client
                     return;
                 }
 
-                _trace.Warning(nameof(MqttClient), exception, "MQTT communication exception while sending/receiving keep alive packets.");
+                _logger.LogWarning(new EventId(), exception, "MQTT communication exception while sending/receiving keep alive packets.");
                 await DisconnectInternalAsync().ConfigureAwait(false);
             }
             catch (Exception exception)
             {
-                _trace.Warning(nameof(MqttClient), exception, "Unhandled exception while sending/receiving keep alive packets.");
+                _logger.LogWarning(new EventId(), exception, "Unhandled exception while sending/receiving keep alive packets.");
                 await DisconnectInternalAsync().ConfigureAwait(false);
             }
             finally
             {
-                _trace.Information(nameof(MqttClient), "Stopped sending keep alive packets.");
+                _logger.LogInformation("Stopped sending keep alive packets.");
             }
         }
 
         private async Task ReceivePackets(CancellationToken cancellationToken)
         {
-            _trace.Information(nameof(MqttClient), "Start receiving packets.");
+            _logger.LogInformation("Start receiving packets.");
 
             try
             {
@@ -437,17 +439,17 @@ namespace MQTTnet.Core.Client
                     return;
                 }
 
-                _trace.Warning(nameof(MqttClient), exception, "MQTT communication exception while receiving packets.");
+                _logger.LogWarning(new EventId(), exception, "MQTT communication exception while receiving packets.");
                 await DisconnectInternalAsync().ConfigureAwait(false);
             }
             catch (Exception exception)
             {
-                _trace.Error(nameof(MqttClient), exception, "Unhandled exception while receiving packets.");
+                _logger.LogError(new EventId(), exception, "Unhandled exception while receiving packets.");
                 await DisconnectInternalAsync().ConfigureAwait(false);
             }
             finally
             {
-                _trace.Information(nameof(MqttClient), "Stopped receiving packets.");
+                _logger.LogInformation(nameof(MqttClient), "Stopped receiving packets.");
             }
         }
 

MQTTnet.Core/Client/MqttPacketDispatcher.cs

@@ -1,10 +1,10 @@
 using System;
+using System.Collections.Concurrent;
 using System.Threading.Tasks;
-using MQTTnet.Core.Diagnostics;
 using MQTTnet.Core.Exceptions;
 using MQTTnet.Core.Internal;
 using MQTTnet.Core.Packets;
-using System.Collections.Concurrent;
+using Microsoft.Extensions.Logging;
 
 namespace MQTTnet.Core.Client
 {
@@ -12,11 +12,11 @@ namespace MQTTnet.Core.Client
     {
         private readonly ConcurrentDictionary<Type, TaskCompletionSource<MqttBasePacket>> _packetByResponseType = new ConcurrentDictionary<Type, TaskCompletionSource<MqttBasePacket>>();
         private readonly ConcurrentDictionary<Type, ConcurrentDictionary<ushort, TaskCompletionSource<MqttBasePacket>>> _packetByResponseTypeAndIdentifier = new ConcurrentDictionary<Type, ConcurrentDictionary<ushort, TaskCompletionSource<MqttBasePacket>>>();
-        private readonly MqttNetTrace _trace;
+        private readonly ILogger<MqttPacketDispatcher> _logger;
 
-        public MqttPacketDispatcher(MqttNetTrace trace)
+        public MqttPacketDispatcher(ILogger<MqttPacketDispatcher> logger)
         {
-            _trace = trace ?? throw new ArgumentNullException(nameof(trace));
+            _logger = logger ?? throw new ArgumentNullException(nameof(logger));
         }
 
         public async Task<MqttBasePacket> WaitForPacketAsync(MqttBasePacket request, Type responseType, TimeSpan timeout)
@@ -30,7 +30,7 @@ namespace MQTTnet.Core.Client
             }
             catch (MqttCommunicationTimedOutException)
             {
-                _trace.Warning(nameof(MqttPacketDispatcher), "Timeout while waiting for packet of type '{0}'.", responseType.Name);
+                _logger.LogWarning("Timeout while waiting for packet of type '{0}'.", responseType.Name);
                 throw;
             }
             finally

MQTTnet.Core/Diagnostics/IMqttNetTraceHandler.cs

@@ -1,9 +0,0 @@
-namespace MQTTnet.Core.Diagnostics
-{
-    public interface IMqttNetTraceHandler
-    {
-        bool IsEnabled { get; }
-
-        void HandleTraceMessage(MqttNetTraceMessage traceMessage);
-    }
-}

MQTTnet.Core/Diagnostics/MqttNetTrace.cs

@@ -1,77 +0,0 @@
-using System;
-
-namespace MQTTnet.Core.Diagnostics
-{
-    public sealed class MqttNetTrace : IMqttNetTraceHandler
-    {
-        private readonly IMqttNetTraceHandler _traceHandler;
-
-        public MqttNetTrace(IMqttNetTraceHandler customTraceHandler = null)
-        {
-            _traceHandler = customTraceHandler ?? this;
-        }
-        
-        public static event EventHandler<MqttNetTraceMessagePublishedEventArgs> TraceMessagePublished;
-
-        public bool IsEnabled => TraceMessagePublished != null;
-
-        public void Verbose(string source, string message, params object[] parameters)
-        {
-            Publish(source, MqttNetTraceLevel.Verbose, null, message, parameters);
-        }
-
-        public void Information(string source, string message, params object[] parameters)
-        {
-            Publish(source, MqttNetTraceLevel.Information, null, message, parameters);
-        }
-
-        public void Warning(string source, string message, params object[] parameters)
-        {
-            Publish(source, MqttNetTraceLevel.Warning, null, message, parameters);
-        }
-
-        public void Warning(string source, Exception exception, string message, params object[] parameters)
-        {
-            Publish(source, MqttNetTraceLevel.Warning, exception, message, parameters);
-        }
-
-        public void Error(string source, string message, params object[] parameters)
-        {
-            Publish(source, MqttNetTraceLevel.Error, null, message, parameters);
-        }
-
-        public void Error(string source, Exception exception, string message, params object[] parameters)
-        {
-            Publish(source, MqttNetTraceLevel.Error, exception, message, parameters);
-        }
-
-        public void HandleTraceMessage(MqttNetTraceMessage mqttNetTraceMessage)
-        {
-            TraceMessagePublished?.Invoke(this, new MqttNetTraceMessagePublishedEventArgs(mqttNetTraceMessage));
-        }
-
-        private void Publish(string source, MqttNetTraceLevel traceLevel, Exception exception, string message, params object[] parameters)
-        {
-            if (!_traceHandler.IsEnabled)
-            {
-                return;
-            }
-
-            var now = DateTime.Now;
-            if (parameters?.Length > 0)
-            {
-                try
-                {
-                    message = string.Format(message, parameters);
-                }
-                catch (Exception formatException)
-                {
-                    Error(nameof(MqttNetTrace), formatException, "Error while tracing message: " + message);
-                    return;
-                }
-            }
-
-            _traceHandler.HandleTraceMessage(new MqttNetTraceMessage(now, Environment.CurrentManagedThreadId, source, traceLevel, message, exception));
-        }
-    }
-}

MQTTnet.Core/Diagnostics/MqttNetTraceLevel.cs

@@ -1,10 +0,0 @@
-namespace MQTTnet.Core.Diagnostics
-{
-    public enum MqttNetTraceLevel
-    {
-        Verbose,
-        Information,
-        Warning,
-        Error
-    }
-}

MQTTnet.Core/Diagnostics/MqttNetTraceMessage.cs

@@ -1,29 +0,0 @@
-using System;
-
-namespace MQTTnet.Core.Diagnostics
-{
-    public sealed class MqttNetTraceMessage
-    {
-        public MqttNetTraceMessage(DateTime timestamp, int threadId, string source, MqttNetTraceLevel level, string message, Exception exception)
-        {
-            Timestamp = timestamp;
-            ThreadId = threadId;
-            Source = source;
-            Level = level;
-            Message = message;
-            Exception = exception;
-        }
-
-        public DateTime Timestamp { get; }
-
-        public int ThreadId { get; }
-
-        public string Source { get; }
-
-        public MqttNetTraceLevel Level { get; }
-
-        public string Message { get; }
-
-        public Exception Exception { get; }
-    }
-}

MQTTnet.Core/Diagnostics/MqttNetTraceMessagePublishedEventArgs.cs

@@ -1,14 +0,0 @@
-using System;
-
-namespace MQTTnet.Core.Diagnostics
-{
-    public sealed class MqttNetTraceMessagePublishedEventArgs : EventArgs
-    {
-        public MqttNetTraceMessagePublishedEventArgs(MqttNetTraceMessage traceMessage)
-        {
-            TraceMessage = traceMessage ?? throw new ArgumentNullException(nameof(traceMessage));
-        }
-
-        public MqttNetTraceMessage TraceMessage { get; }
-    }
-}

MQTTnet.Core/MQTTnet.Core.csproj

@@ -22,4 +22,9 @@
     <PackageLicenseUrl></PackageLicenseUrl>
   </PropertyGroup>
 
+  <ItemGroup>
+    <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" Version="1.1.2" />
+    <PackageReference Include="Microsoft.Extensions.Options" Version="1.1.2" />
+  </ItemGroup>
+
 </Project>

MQTTnet.Core/ManagedClient/ManagedMqttClient.cs

@@ -5,10 +5,10 @@ using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
 using MQTTnet.Core.Client;
-using MQTTnet.Core.Diagnostics;
 using MQTTnet.Core.Exceptions;
 using MQTTnet.Core.Packets;
 using MQTTnet.Core.Protocol;
+using Microsoft.Extensions.Logging;
 
 namespace MQTTnet.Core.ManagedClient
 {
@@ -19,7 +19,7 @@ namespace MQTTnet.Core.ManagedClient
         private readonly HashSet<TopicFilter> _subscriptions = new HashSet<TopicFilter>();
 
         private readonly IMqttClient _mqttClient;
-        private readonly MqttNetTrace _trace;
+        private readonly ILogger<ManagedMqttClient> _logger;
 
         private CancellationTokenSource _connectionCancellationToken;
         private CancellationTokenSource _publishingCancellationToken;
@@ -27,12 +27,11 @@ namespace MQTTnet.Core.ManagedClient
         private IManagedMqttClientOptions _options;
         private bool _subscriptionsNotPushed;
         
-        public ManagedMqttClient(IMqttCommunicationAdapterFactory communicationChannelFactory, MqttNetTrace trace)
+        public ManagedMqttClient(ILogger<ManagedMqttClient> logger, IMqttClient mqttClient)
         {
-            if (communicationChannelFactory == null) throw new ArgumentNullException(nameof(communicationChannelFactory));
-            _trace = trace ?? throw new ArgumentNullException(nameof(trace));
+            _logger = logger ?? throw new ArgumentNullException(nameof(logger));
+            _mqttClient = mqttClient ?? throw new ArgumentNullException(nameof(mqttClient));
 
-            _mqttClient = new MqttClient(communicationChannelFactory, _trace);
             _mqttClient.Connected += OnConnected;
             _mqttClient.Disconnected += OnDisconnected;
             _mqttClient.ApplicationMessageReceived += OnApplicationMessageReceived;
@@ -77,7 +76,7 @@ namespace MQTTnet.Core.ManagedClient
             Task.Factory.StartNew(() => MaintainConnectionAsync(_connectionCancellationToken.Token), _connectionCancellationToken.Token, TaskCreationOptions.LongRunning, TaskScheduler.Default).ConfigureAwait(false);
 #pragma warning restore CS4014 // Because this call is not awaited, execution of the current method continues before the call is completed
 
-            _trace.Information(nameof(ManagedMqttClient), "Started");
+            _logger.LogInformation("Started");
         }
 
         public Task StopAsync()
@@ -179,16 +178,16 @@ namespace MQTTnet.Core.ManagedClient
             }
             catch (MqttCommunicationException exception)
             {
-                _trace.Warning(nameof(ManagedMqttClient), exception, "Communication exception while maintaining connection.");
+                _logger.LogWarning(new EventId(), exception, "Communication exception while maintaining connection.");
             }
             catch (Exception exception)
             {
-                _trace.Error(nameof(ManagedMqttClient), exception, "Unhandled exception while maintaining connection.");
+                _logger.LogError(new EventId(), exception, "Unhandled exception while maintaining connection.");
             }
             finally
             {
                 await _mqttClient.DisconnectAsync().ConfigureAwait(false);
-                _trace.Information(nameof(ManagedMqttClient), "Stopped");
+                _logger.LogInformation("Stopped");
             }
         }
 
@@ -217,7 +216,7 @@ namespace MQTTnet.Core.ManagedClient
             }
             finally
             {
-                _trace.Information(nameof(ManagedMqttClient), "Stopped publishing messages");
+                _logger.LogInformation("Stopped publishing messages");
             }
         }
 
@@ -229,7 +228,7 @@ namespace MQTTnet.Core.ManagedClient
             }
             catch (MqttCommunicationException exception)
             {
-                _trace.Warning(nameof(ManagedMqttClient), exception, "Publishing application message failed.");
+                _logger.LogWarning(new EventId(), exception, "Publishing application message failed.");
 
                 if (message.QualityOfServiceLevel > MqttQualityOfServiceLevel.AtMostOnce)
                 {
@@ -238,13 +237,13 @@ namespace MQTTnet.Core.ManagedClient
             }
             catch (Exception exception)
             {
-                _trace.Error(nameof(ManagedMqttClient), exception, "Unhandled exception while publishing queued application message.");
+                _logger.LogError(new EventId(), exception, "Unhandled exception while publishing queued application message.");
             }
         }
 
         private async Task PushSubscriptionsAsync()
         {
-            _trace.Information(nameof(ManagedMqttClient), "Synchronizing subscriptions");
+            _logger.LogInformation(nameof(ManagedMqttClient), "Synchronizing subscriptions");
 
             List<TopicFilter> subscriptions;
             lock (_subscriptions)
@@ -264,7 +263,7 @@ namespace MQTTnet.Core.ManagedClient
             }
             catch (Exception exception)
             {
-                _trace.Warning(nameof(ManagedMqttClient), exception, "Synchronizing subscriptions failed");
+                _logger.LogWarning(new EventId(), exception, "Synchronizing subscriptions failed");
                 _subscriptionsNotPushed = true;
             }
         }

MQTTnet.Core/Server/IMqttClientSesssionFactory.cs

@@ -0,0 +1,7 @@
+namespace MQTTnet.Core.Server
+{
+    public interface IMqttClientSesssionFactory
+    {
+        MqttClientSession CreateClientSession(string sessionId, MqttClientSessionsManager mqttClientSessionsManager);
+    }
+}

MQTTnet.Core/Server/IMqttServerFactory.cs

@@ -1,9 +1,7 @@
-using MQTTnet.Core.Diagnostics;
-
-namespace MQTTnet.Core.Server
+namespace MQTTnet.Core.Server
 {
     public interface IMqttServerFactory
     {
-        IMqttServer CreateMqttServer(MqttServerOptions options, IMqttNetTraceHandler traceHandler = null);
+        IMqttServer CreateMqttServer();
     }
 }

MQTTnet.Core/Server/MqttClientPendingMessagesQueue.cs

@@ -3,10 +3,10 @@ using System.Collections.Concurrent;
 using System.Threading;
 using System.Threading.Tasks;
 using MQTTnet.Core.Adapter;
-using MQTTnet.Core.Diagnostics;
 using MQTTnet.Core.Exceptions;
 using MQTTnet.Core.Packets;
 using MQTTnet.Core.Protocol;
+using Microsoft.Extensions.Logging;
 
 namespace MQTTnet.Core.Server
 {
@@ -15,11 +15,11 @@ namespace MQTTnet.Core.Server
         private readonly BlockingCollection<MqttPublishPacket> _pendingPublishPackets = new BlockingCollection<MqttPublishPacket>();
         private readonly MqttClientSession _session;
         private readonly MqttServerOptions _options;
-        private readonly MqttNetTrace _trace;
+        private readonly ILogger<MqttClientPendingMessagesQueue> _logger;
 
-        public MqttClientPendingMessagesQueue(MqttServerOptions options, MqttClientSession session, MqttNetTrace trace)
+        public MqttClientPendingMessagesQueue(MqttServerOptions options, MqttClientSession session, ILogger<MqttClientPendingMessagesQueue> logger)
         {
-            _trace = trace ?? throw new ArgumentNullException(nameof(trace));
+            _logger = logger ?? throw new ArgumentNullException(nameof(logger));
             _session = session ?? throw new ArgumentNullException(nameof(session));
             _options = options ?? throw new ArgumentNullException(nameof(options));
         }
@@ -52,7 +52,7 @@ namespace MQTTnet.Core.Server
             }
             catch (Exception exception)
             {
-                _trace.Error(nameof(MqttClientPendingMessagesQueue), exception, "Unhandled exception while sending pending publish packets.");
+                _logger.LogError(new EventId(), exception, "Unhandled exception while sending pending publish packets.");
             }
         }
 
@@ -68,18 +68,18 @@ namespace MQTTnet.Core.Server
             {
                 if (exception is MqttCommunicationTimedOutException)
                 {
-                    _trace.Warning(nameof(MqttClientPendingMessagesQueue), exception, "Sending publish packet failed due to timeout.");
+                    _logger.LogWarning(new EventId(), exception, "Sending publish packet failed due to timeout.");
                 }
                 else if (exception is MqttCommunicationException)
                 {
-                    _trace.Warning(nameof(MqttClientPendingMessagesQueue), exception, "Sending publish packet failed due to communication exception.");
+                    _logger.LogWarning(new EventId(), exception, "Sending publish packet failed due to communication exception.");
                 }
                 if (exception is OperationCanceledException)
                 {
                 }
                 else
                 {
-                    _trace.Error(nameof(MqttClientPendingMessagesQueue), exception, "Sending publish packet failed.");
+                    _logger.LogError(new EventId(), exception, "Sending publish packet failed.");
                 }
 
                 if (packet.QualityOfServiceLevel > MqttQualityOfServiceLevel.AtMostOnce)

MQTTnet.Core/Server/MqttClientRetainedMessagesManager.cs

@@ -2,21 +2,22 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Threading.Tasks;
-using MQTTnet.Core.Diagnostics;
 using MQTTnet.Core.Packets;
+using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Options;
 
 namespace MQTTnet.Core.Server
 {
     public sealed class MqttClientRetainedMessagesManager
     {
         private readonly Dictionary<string, MqttApplicationMessage> _retainedMessages = new Dictionary<string, MqttApplicationMessage>();
-        private readonly MqttNetTrace _trace;
+        private readonly ILogger<MqttClientRetainedMessagesManager> _logger;
         private readonly MqttServerOptions _options;
 
-        public MqttClientRetainedMessagesManager(MqttServerOptions options, MqttNetTrace trace)
+        public MqttClientRetainedMessagesManager(IOptions<MqttServerOptions> options, ILogger<MqttClientRetainedMessagesManager> logger)
         {
-            _trace = trace ?? throw new ArgumentNullException(nameof(trace));
-            _options = options ?? throw new ArgumentNullException(nameof(options));
+            _logger = logger ?? throw new ArgumentNullException(nameof(logger));
+            _options = options.Value ?? throw new ArgumentNullException(nameof(options));
         }
 
         public async Task LoadMessagesAsync()
@@ -40,7 +41,7 @@ namespace MQTTnet.Core.Server
             }
             catch (Exception exception)
             {
-                _trace.Error(nameof(MqttClientRetainedMessagesManager), exception, "Unhandled exception while loading retained messages.");
+                _logger.LogError(new EventId(), exception, "Unhandled exception while loading retained messages.");
             }
         }
 
@@ -54,12 +55,12 @@ namespace MQTTnet.Core.Server
                 if (applicationMessage.Payload?.Any() == false)
                 {
                     _retainedMessages.Remove(applicationMessage.Topic);
-                    _trace.Information(nameof(MqttClientRetainedMessagesManager), "Client '{0}' cleared retained message for topic '{1}'.", clientId, applicationMessage.Topic);
+                    _logger.LogInformation("Client '{0}' cleared retained message for topic '{1}'.", clientId, applicationMessage.Topic);
                 }
                 else
                 {
                     _retainedMessages[applicationMessage.Topic] = applicationMessage;
-                    _trace.Information(nameof(MqttClientRetainedMessagesManager), "Client '{0}' updated retained message for topic '{1}'.", clientId, applicationMessage.Topic);
+                    _logger.LogInformation("Client '{0}' updated retained message for topic '{1}'.", clientId, applicationMessage.Topic);
                 }
 
                 allRetainedMessages = new List<MqttApplicationMessage>(_retainedMessages.Values);
@@ -75,7 +76,7 @@ namespace MQTTnet.Core.Server
             }
             catch (Exception exception)
             {
-                _trace.Error(nameof(MqttClientRetainedMessagesManager), exception, "Unhandled exception while saving retained messages.");
+                _logger.LogError(new EventId(), exception, "Unhandled exception while saving retained messages.");
             }
         }
 

MQTTnet.Core/Server/MqttClientSession.cs

@@ -3,12 +3,12 @@ using System.Collections.Generic;
 using System.Threading;
 using System.Threading.Tasks;
 using MQTTnet.Core.Adapter;
-using MQTTnet.Core.Diagnostics;
 using MQTTnet.Core.Exceptions;
 using MQTTnet.Core.Internal;
 using MQTTnet.Core.Packets;
 using MQTTnet.Core.Protocol;
 using MQTTnet.Core.Serializer;
+using Microsoft.Extensions.Logging;
 
 namespace MQTTnet.Core.Server
 {
@@ -20,19 +20,20 @@ namespace MQTTnet.Core.Server
         private readonly MqttClientSessionsManager _mqttClientSessionsManager;
         private readonly MqttClientPendingMessagesQueue _pendingMessagesQueue;
         private readonly MqttServerOptions _options;
-        private readonly MqttNetTrace _trace;
+        private readonly ILogger<MqttClientSession> _logger;
 
         private IMqttCommunicationAdapter _adapter;
         private CancellationTokenSource _cancellationTokenSource;
         private MqttApplicationMessage _willMessage;
 
-        public MqttClientSession(string clientId, MqttServerOptions options, MqttClientSessionsManager mqttClientSessionsManager, MqttNetTrace trace)
+        public MqttClientSession(string clientId, MqttClientSessionsManager mqttClientSessionsManager, ILogger<MqttClientSession> logger, ILogger<MqttClientPendingMessagesQueue> msgQueueLogger)
         {
-            _trace = trace ?? throw new ArgumentNullException(nameof(trace));
             ClientId = clientId;
-            _options = options ?? throw new ArgumentNullException(nameof(options));
+            _options = mqttClientSessionsManager.Options;
             _mqttClientSessionsManager = mqttClientSessionsManager ?? throw new ArgumentNullException(nameof(mqttClientSessionsManager));
-            _pendingMessagesQueue = new MqttClientPendingMessagesQueue(options, this, trace);
+            _logger = logger ?? throw new ArgumentNullException(nameof(logger));
+
+            _pendingMessagesQueue = new MqttClientPendingMessagesQueue(mqttClientSessionsManager.Options, this, msgQueueLogger);
         }
 
         public string ClientId { get; }
@@ -60,11 +61,11 @@ namespace MQTTnet.Core.Server
             }
             catch (MqttCommunicationException exception)
             {
-                _trace.Warning(nameof(MqttClientSession), exception, "Client '{0}': Communication exception while processing client packets.", ClientId);
+                _logger.LogWarning(new EventId(), exception, "Client '{0}': Communication exception while processing client packets.", ClientId);
             }
             catch (Exception exception)
             {
-                _trace.Error(nameof(MqttClientSession), exception, "Client '{0}': Unhandled exception while processing client packets.", ClientId);
+                _logger.LogError(new EventId(), exception, "Client '{0}': Unhandled exception while processing client packets.", ClientId);
             }
         }
 
@@ -81,7 +82,7 @@ namespace MQTTnet.Core.Server
 
             _adapter = null;
 
-            _trace.Information(nameof(MqttClientSession), "Client '{0}': Disconnected.", ClientId);
+            _logger.LogInformation("Client '{0}': Disconnected.", ClientId);
         }
 
         public void EnqueuePublishPacket(MqttPublishPacket publishPacket)
@@ -94,7 +95,7 @@ namespace MQTTnet.Core.Server
             }
 
             _pendingMessagesQueue.Enqueue(publishPacket);
-            _trace.Verbose(nameof(MqttClientSession), "Client '{0}': Enqueued pending publish packet.", ClientId);
+            _logger.LogTrace("Client '{0}': Enqueued pending publish packet.", ClientId);
         }
 
         public void Dispose()
@@ -118,12 +119,12 @@ namespace MQTTnet.Core.Server
             }
             catch (MqttCommunicationException exception)
             {
-                _trace.Warning(nameof(MqttClientSession), exception, "Client '{0}': Communication exception while processing client packets.", ClientId);
+                _logger.LogWarning(new EventId(), exception, "Client '{0}': Communication exception while processing client packets.", ClientId);
                 Stop();
             }
             catch (Exception exception)
             {
-                _trace.Error(nameof(MqttClientSession), exception, "Client '{0}': Unhandled exception while processing client packets.", ClientId);
+                _logger.LogError(new EventId(), exception, "Client '{0}': Unhandled exception while processing client packets.", ClientId);
                 Stop();
             }
         }
@@ -165,7 +166,7 @@ namespace MQTTnet.Core.Server
             }
             else
             {
-                _trace.Warning(nameof(MqttClientSession), "Client '{0}': Received not supported packet ({1}). Closing connection.", ClientId, packet);
+                _logger.LogWarning("Client '{0}': Received not supported packet ({1}). Closing connection.", ClientId, packet);
                 Stop();
             }
         }

MQTTnet.Core/Server/MqttClientSessionsManager.cs

@@ -4,26 +4,28 @@ using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
 using MQTTnet.Core.Adapter;
-using MQTTnet.Core.Diagnostics;
 using MQTTnet.Core.Exceptions;
 using MQTTnet.Core.Internal;
 using MQTTnet.Core.Packets;
 using MQTTnet.Core.Protocol;
 using MQTTnet.Core.Serializer;
+using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Options;
 
 namespace MQTTnet.Core.Server
 {
     public sealed class MqttClientSessionsManager
     {
         private readonly Dictionary<string, MqttClientSession> _clientSessions = new Dictionary<string, MqttClientSession>();
-        private readonly MqttServerOptions _options;
-        private readonly MqttNetTrace _trace;
+        private readonly ILogger<MqttClientSessionsManager> _logger;
+        private readonly IMqttClientSesssionFactory _mqttClientSesssionFactory;
 
-        public MqttClientSessionsManager(MqttServerOptions options, MqttNetTrace trace)
+        public MqttClientSessionsManager(IOptions<MqttServerOptions> options, ILogger<MqttClientSessionsManager> logger, MqttClientRetainedMessagesManager retainedMessagesManager, IMqttClientSesssionFactory mqttClientSesssionFactory)
         {
-            _trace = trace ?? throw new ArgumentNullException(nameof(trace));
-            _options = options ?? throw new ArgumentNullException(nameof(options));
-            RetainedMessagesManager = new MqttClientRetainedMessagesManager(options, trace);
+            _logger = logger ?? throw new ArgumentNullException(nameof(logger));
+            Options = options.Value ?? throw new ArgumentNullException(nameof(options));
+            RetainedMessagesManager = retainedMessagesManager ?? throw new ArgumentNullException(nameof(options));
+            _mqttClientSesssionFactory = mqttClientSesssionFactory ?? throw new ArgumentNullException(nameof(mqttClientSesssionFactory));
         }
 
         public event EventHandler<MqttApplicationMessageReceivedEventArgs> ApplicationMessageReceived;
@@ -31,13 +33,14 @@ namespace MQTTnet.Core.Server
         public event EventHandler<MqttClientDisconnectedEventArgs> ClientDisconnected;
 
         public MqttClientRetainedMessagesManager RetainedMessagesManager { get; }
+        public MqttServerOptions Options { get; }
 
         public async Task RunClientSessionAsync(IMqttCommunicationAdapter clientAdapter)
         {
             var clientId = string.Empty;
             try
             {
-                if (!(await clientAdapter.ReceivePacketAsync(_options.DefaultCommunicationTimeout, CancellationToken.None).ConfigureAwait(false) is MqttConnectPacket connectPacket))
+                if (!(await clientAdapter.ReceivePacketAsync(Options.DefaultCommunicationTimeout, CancellationToken.None).ConfigureAwait(false) is MqttConnectPacket connectPacket))
                 {
                     throw new MqttProtocolViolationException("The first packet from a client must be a 'CONNECT' packet [MQTT-3.1.0-1].");
                 }
@@ -50,7 +53,7 @@ namespace MQTTnet.Core.Server
                 var connectReturnCode = ValidateConnection(connectPacket);
                 if (connectReturnCode != MqttConnectReturnCode.ConnectionAccepted)
                 {
-                    await clientAdapter.SendPacketsAsync(_options.DefaultCommunicationTimeout, CancellationToken.None, new MqttConnAckPacket
+                    await clientAdapter.SendPacketsAsync(Options.DefaultCommunicationTimeout, CancellationToken.None, new MqttConnAckPacket
                     {
                         ConnectReturnCode = connectReturnCode
                     }).ConfigureAwait(false);
@@ -60,7 +63,7 @@ namespace MQTTnet.Core.Server
 
                 var clientSession = GetOrCreateClientSession(connectPacket);
 
-                await clientAdapter.SendPacketsAsync(_options.DefaultCommunicationTimeout, CancellationToken.None, new MqttConnAckPacket
+                await clientAdapter.SendPacketsAsync(Options.DefaultCommunicationTimeout, CancellationToken.None, new MqttConnAckPacket
                 {
                     ConnectReturnCode = connectReturnCode,
                     IsSessionPresent = clientSession.IsExistingSession
@@ -72,17 +75,20 @@ namespace MQTTnet.Core.Server
                     ProtocolVersion = clientAdapter.PacketSerializer.ProtocolVersion
                 }));
 
-                await clientSession.Session.RunAsync(connectPacket.WillMessage, clientAdapter).ConfigureAwait(false);
+                using (_logger.BeginScope(clientId))
+                {
+                    await clientSession.Session.RunAsync(connectPacket.WillMessage, clientAdapter).ConfigureAwait(false);
+                }
             }
             catch (Exception exception)
             {
-                _trace.Error(nameof(MqttServer), exception, exception.Message);
+                _logger.LogError(new EventId(), exception, exception.Message);
             }
             finally
             {
                 try
                 {
-                    await clientAdapter.DisconnectAsync(_options.DefaultCommunicationTimeout).ConfigureAwait(false);
+                    await clientAdapter.DisconnectAsync(Options.DefaultCommunicationTimeout).ConfigureAwait(false);
                 }
                 catch (Exception)
                 {
@@ -126,7 +132,7 @@ namespace MQTTnet.Core.Server
             }
             catch (Exception exception)
             {
-                _trace.Error(nameof(MqttClientSessionsManager), exception, "Error while processing application message");
+                _logger.LogError(new EventId(), exception, "Error while processing application message");
             }
 
             lock (_clientSessions)
@@ -140,9 +146,9 @@ namespace MQTTnet.Core.Server
 
         private MqttConnectReturnCode ValidateConnection(MqttConnectPacket connectPacket)
         {
-            if (_options.ConnectionValidator != null)
+            if (Options.ConnectionValidator != null)
             {
-                return _options.ConnectionValidator(connectPacket);
+                return Options.ConnectionValidator(connectPacket);
             }
 
             return MqttConnectReturnCode.ConnectionAccepted;
@@ -160,11 +166,11 @@ namespace MQTTnet.Core.Server
                         _clientSessions.Remove(connectPacket.ClientId);
                         clientSession.Dispose();
                         clientSession = null;
-                        _trace.Verbose(nameof(MqttClientSessionsManager), "Disposed existing session of client '{0}'.", connectPacket.ClientId);
+                        _logger.LogTrace("Disposed existing session of client '{0}'.", connectPacket.ClientId);
                     }
                     else
                     {
-                        _trace.Verbose(nameof(MqttClientSessionsManager), "Reusing existing session of client '{0}'.", connectPacket.ClientId);
+                        _logger.LogTrace("Reusing existing session of client '{0}'.", connectPacket.ClientId);
                     }
                 }
 
@@ -173,10 +179,10 @@ namespace MQTTnet.Core.Server
                 {
                     isExistingSession = false;
 
-                    clientSession = new MqttClientSession(connectPacket.ClientId, _options, this, _trace);
+                    clientSession = _mqttClientSesssionFactory.CreateClientSession(connectPacket.ClientId, this);
                     _clientSessions[connectPacket.ClientId] = clientSession;
 
-                    _trace.Verbose(nameof(MqttClientSessionsManager), "Created a new session for client '{0}'.", connectPacket.ClientId);
+                    _logger.LogTrace("Created a new session for client '{0}'.", connectPacket.ClientId);
                 }
 
                 return new GetOrCreateClientSessionResult { IsExistingSession = isExistingSession, Session = clientSession };

MQTTnet.Core/Server/MqttServer.cs

@@ -3,26 +3,33 @@ using System.Collections.Generic;
 using System.Threading;
 using System.Threading.Tasks;
 using MQTTnet.Core.Adapter;
-using MQTTnet.Core.Diagnostics;
+using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Options;
+using System.Linq;
 
 namespace MQTTnet.Core.Server
 {
     public sealed class MqttServer : IMqttServer
     {
-        private readonly MqttNetTrace _trace;
+        private readonly ILogger<MqttServer> _logger;
         private readonly MqttClientSessionsManager _clientSessionsManager;
         private readonly ICollection<IMqttServerAdapter> _adapters;
         private readonly MqttServerOptions _options;
 
         private CancellationTokenSource _cancellationTokenSource;
 
-        public MqttServer(MqttServerOptions options, ICollection<IMqttServerAdapter> adapters, MqttNetTrace trace)
+        public MqttServer(IOptions<MqttServerOptions> options, IEnumerable<IMqttServerAdapter> adapters, ILogger<MqttServer> logger, MqttClientSessionsManager clientSessionsManager)
         {
-            _trace = trace ?? throw new ArgumentNullException(nameof(trace));
-            _options = options ?? throw new ArgumentNullException(nameof(options));
-            _adapters = adapters ?? throw new ArgumentNullException(nameof(adapters));
+            _options = options.Value ?? throw new ArgumentNullException(nameof(options));
+            _logger = logger ?? throw new ArgumentNullException(nameof(logger));
+            _clientSessionsManager = clientSessionsManager ?? throw new ArgumentNullException(nameof(clientSessionsManager));
+
+            if (adapters == null)
+            {
+                throw new ArgumentNullException(nameof(adapters));
+            }            
+            _adapters = adapters.ToList();
 
-            _clientSessionsManager = new MqttClientSessionsManager(options, trace);
             _clientSessionsManager.ApplicationMessageReceived += (s, e) => ApplicationMessageReceived?.Invoke(s, e);
             _clientSessionsManager.ClientConnected += OnClientConnected;
             _clientSessionsManager.ClientDisconnected += OnClientDisconnected;
@@ -59,7 +66,7 @@ namespace MQTTnet.Core.Server
                 await adapter.StartAsync(_options);
             }
 
-            _trace.Information(nameof(MqttServer), "Started.");
+            _logger.LogInformation("Started.");
         }
 
         public async Task StopAsync()
@@ -76,7 +83,7 @@ namespace MQTTnet.Core.Server
 
             _clientSessionsManager.Clear();
 
-            _trace.Information(nameof(MqttServer), "Stopped.");
+            _logger.LogInformation("Stopped.");
         }
 
         private void OnClientAccepted(object sender, MqttServerAdapterClientAcceptedEventArgs eventArgs)
@@ -86,13 +93,13 @@ namespace MQTTnet.Core.Server
 
         private void OnClientConnected(object sender, MqttClientConnectedEventArgs eventArgs)
         {
-            _trace.Information(nameof(MqttServer), "Client '{0}': Connected.", eventArgs.Client.ClientId);
+            _logger.LogInformation("Client '{0}': Connected.", eventArgs.Client.ClientId);
             ClientConnected?.Invoke(this, eventArgs);
         }
 
         private void OnClientDisconnected(object sender, MqttClientDisconnectedEventArgs eventArgs)
         {
-            _trace.Information(nameof(MqttServer), "Client '{0}': Disconnected.", eventArgs.Client.ClientId);
+            _logger.LogInformation("Client '{0}': Disconnected.", eventArgs.Client.ClientId);
             ClientDisconnected?.Invoke(this, eventArgs);
         }
     }

Tests/MQTTnet.Core.Tests/MQTTnet.Core.Tests.csproj

@@ -7,6 +7,7 @@
   </PropertyGroup>
 
   <ItemGroup>
+    <PackageReference Include="Microsoft.Extensions.Logging" Version="1.1.2" />
     <PackageReference Include="MSTest.TestAdapter" Version="1.1.18" />
     <PackageReference Include="MSTest.TestFramework" Version="1.1.18" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.3.0" />

Tests/MQTTnet.Core.Tests/MqttCommunicationAdapterFactory.cs

@@ -1,4 +1,5 @@
 using MQTTnet.Core.Adapter;
+using MQTTnet.Core.Channel;
 using MQTTnet.Core.Client;
 
 namespace MQTTnet.Core.Tests
@@ -12,7 +13,12 @@ namespace MQTTnet.Core.Tests
             _adapter = adapter;
         }
 
-        public IMqttCommunicationAdapter CreateMqttCommunicationAdapter(IMqttClientOptions options)
+        public IMqttCommunicationAdapter CreateClientMqttCommunicationAdapter(IMqttClientOptions options)
+        {
+            return _adapter;
+        }
+
+        public IMqttCommunicationAdapter CreateServerMqttCommunicationAdapter(IMqttCommunicationChannel channel)
         {
             return _adapter;
         }

Tests/MQTTnet.Core.Tests/MqttServerTests.cs

@@ -5,10 +5,10 @@ using System.Threading.Tasks;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 using MQTTnet.Core.Adapter;
 using MQTTnet.Core.Client;
-using MQTTnet.Core.Diagnostics;
 using MQTTnet.Core.Packets;
 using MQTTnet.Core.Protocol;
 using MQTTnet.Core.Server;
+using Microsoft.Extensions.DependencyInjection;
 
 namespace MQTTnet.Core.Tests
 {
@@ -52,7 +52,12 @@ namespace MQTTnet.Core.Tests
         public async Task MqttServer_WillMessage()
         {
             var serverAdapter = new TestMqttServerAdapter();
-            var s = new MqttServer(new MqttServerOptions(), new List<IMqttServerAdapter> { serverAdapter }, new MqttNetTrace());
+            var services = new ServiceCollection()
+                .AddMqttServer()
+                .AddSingleton<IMqttServerAdapter>(serverAdapter)
+                .BuildServiceProvider();
+
+            var s = services.GetRequiredService<IMqttServer>();
             await s.StartAsync();
 
             var willMessage = new MqttApplicationMessageBuilder().WithTopic("My/last/will").WithAtMostOnceQoS().Build();
@@ -76,7 +81,12 @@ namespace MQTTnet.Core.Tests
         public async Task MqttServer_Unsubscribe()
         {
             var serverAdapter = new TestMqttServerAdapter();
-            var s = new MqttServer(new MqttServerOptions(), new List<IMqttServerAdapter> { serverAdapter }, new MqttNetTrace());
+            var services = new ServiceCollection()
+                .AddMqttServer()
+                .AddSingleton<IMqttServerAdapter>(serverAdapter)
+                .BuildServiceProvider();
+
+            var s = services.GetRequiredService<IMqttServer>();
             await s.StartAsync();
 
             var c1 = await serverAdapter.ConnectTestClient(s, "c1");
@@ -112,7 +122,12 @@ namespace MQTTnet.Core.Tests
         public async Task MqttServer_Publish()
         {
             var serverAdapter = new TestMqttServerAdapter();
-            var s = new MqttServer(new MqttServerOptions(), new List<IMqttServerAdapter> { serverAdapter }, new MqttNetTrace());
+            var services = new ServiceCollection()
+                .AddMqttServer()
+                .AddSingleton<IMqttServerAdapter>(serverAdapter)
+                .BuildServiceProvider();
+
+            var s = services.GetRequiredService<IMqttServer>();
             await s.StartAsync();
 
             var c1 = await serverAdapter.ConnectTestClient(s, "c1");
@@ -135,7 +150,12 @@ namespace MQTTnet.Core.Tests
         public async Task MqttServer_NoRetainedMessage()
         {
             var serverAdapter = new TestMqttServerAdapter();
-            var s = new MqttServer(new MqttServerOptions(), new List<IMqttServerAdapter> { serverAdapter }, new MqttNetTrace());
+            var services = new ServiceCollection()
+                .AddMqttServer()
+                .AddSingleton<IMqttServerAdapter>(serverAdapter)
+                .BuildServiceProvider();
+
+            var s = services.GetRequiredService<IMqttServer>();
             await s.StartAsync();
 
             var c1 = await serverAdapter.ConnectTestClient(s, "c1");
@@ -158,7 +178,12 @@ namespace MQTTnet.Core.Tests
         public async Task MqttServer_RetainedMessage()
         {
             var serverAdapter = new TestMqttServerAdapter();
-            var s = new MqttServer(new MqttServerOptions(), new List<IMqttServerAdapter> { serverAdapter }, new MqttNetTrace());
+            var services = new ServiceCollection()
+                .AddMqttServer()
+                .AddSingleton<IMqttServerAdapter>(serverAdapter)
+                .BuildServiceProvider();
+
+            var s = services.GetRequiredService<IMqttServer>();
             await s.StartAsync();
 
             var c1 = await serverAdapter.ConnectTestClient(s, "c1");
@@ -181,7 +206,12 @@ namespace MQTTnet.Core.Tests
         public async Task MqttServer_ClearRetainedMessage()
         {
             var serverAdapter = new TestMqttServerAdapter();
-            var s = new MqttServer(new MqttServerOptions(), new List<IMqttServerAdapter> { serverAdapter }, new MqttNetTrace());
+            var services = new ServiceCollection()
+                .AddMqttServer()
+                .AddSingleton<IMqttServerAdapter>(serverAdapter)
+                .BuildServiceProvider();
+
+            var s = services.GetRequiredService<IMqttServer>();
             await s.StartAsync();
 
             var c1 = await serverAdapter.ConnectTestClient(s, "c1");
@@ -207,7 +237,12 @@ namespace MQTTnet.Core.Tests
             var storage = new TestStorage();
 
             var serverAdapter = new TestMqttServerAdapter();
-            var s = new MqttServer(new MqttServerOptions { Storage = storage }, new List<IMqttServerAdapter> { serverAdapter }, new MqttNetTrace());
+            var services = new ServiceCollection()
+                .AddMqttServer()
+                .AddSingleton<IMqttServerAdapter>(serverAdapter)
+                .BuildServiceProvider();
+
+            var s = services.GetRequiredService<IMqttServer>();
             await s.StartAsync();
 
             var c1 = await serverAdapter.ConnectTestClient(s, "c1");
@@ -216,7 +251,7 @@ namespace MQTTnet.Core.Tests
 
             await s.StopAsync();
 
-            s = new MqttServer(new MqttServerOptions { Storage = storage }, new List<IMqttServerAdapter> { serverAdapter }, new MqttNetTrace());
+            s = services.GetRequiredService<IMqttServer>();
             await s.StartAsync();
 
             var c2 = await serverAdapter.ConnectTestClient(s, "c2");
@@ -244,7 +279,12 @@ namespace MQTTnet.Core.Tests
             };
 
             var serverAdapter = new TestMqttServerAdapter();
-            var s = new MqttServer(options, new List<IMqttServerAdapter> { serverAdapter }, new MqttNetTrace());
+            var services = new ServiceCollection()
+                .AddMqttServer()
+                .AddSingleton<IMqttServerAdapter>(serverAdapter)
+                .BuildServiceProvider();
+
+            var s = services.GetRequiredService<IMqttServer>();
             await s.StartAsync();
 
             var c1 = await serverAdapter.ConnectTestClient(s, "c1");
@@ -290,7 +330,12 @@ namespace MQTTnet.Core.Tests
             int expectedReceivedMessagesCount)
         {
             var serverAdapter = new TestMqttServerAdapter();
-            var s = new MqttServer(new MqttServerOptions(), new List<IMqttServerAdapter> { serverAdapter }, new MqttNetTrace());
+            var services = new ServiceCollection()
+                .AddMqttServer()
+                .AddSingleton<IMqttServerAdapter>(serverAdapter)
+                .BuildServiceProvider();
+
+            var s = services.GetRequiredService<IMqttServer>();
             await s.StartAsync();
 
             var c1 = await serverAdapter.ConnectTestClient(s, "c1");

Tests/MQTTnet.Core.Tests/ServiceCollectionTest.cs

@@ -0,0 +1,30 @@
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace MQTTnet.Core.Tests
+{
+    [TestClass]
+    public class ServiceCollectionTest
+    {
+        [TestMethod]
+        public void TestCanConstructAllServices()
+        {
+            var services = new ServiceCollection()
+                .AddLogging()
+                .AddMqttServer()
+                .AddMqttClient();
+
+            var serviceProvider = services
+                .BuildServiceProvider();
+
+            foreach (var service in services)
+            {
+                if (service.ServiceType.IsGenericType)
+                {
+                    continue;
+                }
+                serviceProvider.GetRequiredService(service.ServiceType);
+            }
+        }
+    }
+}

Tests/MQTTnet.Core.Tests/TestClientSessionFactory.cs

@@ -0,0 +1,12 @@
+using MQTTnet.Core.Server;
+
+namespace MQTTnet.Core.Tests
+{
+    public class TestClientSessionFactory : IMqttClientSesssionFactory
+    {
+        public MqttClientSession CreateClientSession(string sessionId, MqttClientSessionsManager mqttClientSessionsManager)
+        {
+            return new MqttClientSession(sessionId, mqttClientSessionsManager, new TestLogger<MqttClientSession>(), new TestLogger<MqttClientPendingMessagesQueue>());
+        }
+    }
+}

Tests/MQTTnet.Core.Tests/TestLogger.cs

@@ -0,0 +1,22 @@
+using Microsoft.Extensions.Logging;
+using System;
+
+namespace MQTTnet.Core.Tests
+{
+    public class TestLogger<T> : ILogger<T>
+    {
+        public IDisposable BeginScope<TState>(TState state)
+        {
+            throw new NotImplementedException();
+        }
+
+        public bool IsEnabled(LogLevel logLevel)
+        {
+            return true;
+        }
+
+        public void Log<TState>(LogLevel logLevel, EventId eventId, TState state, Exception exception, Func<TState, Exception, string> formatter)
+        {
+        }
+    }
+}

Tests/MQTTnet.Core.Tests/TestMqttServerAdapter.cs

@@ -3,7 +3,6 @@ using System.Threading.Tasks;
 using MQTTnet.Core.Adapter;
 using MQTTnet.Core.Server;
 using MQTTnet.Core.Client;
-using MQTTnet.Core.Diagnostics;
 
 namespace MQTTnet.Core.Tests
 {
@@ -18,7 +17,7 @@ namespace MQTTnet.Core.Tests
             adapterA.Partner = adapterB;
             adapterB.Partner = adapterA;
 
-            var client = new MqttClient(new MqttCommunicationAdapterFactory(adapterA), new MqttNetTrace());
+            var client = new MqttClient(new MqttCommunicationAdapterFactory(adapterA), new TestLogger<MqttClient>(), new MqttPacketDispatcher(new TestLogger<MqttPacketDispatcher>()));
             var connected = WaitForClientToConnect(server, clientId);
 
             FireClientAcceptedEvent(adapterB);

Tests/MQTTnet.TestApp.AspNetCore2/MqttWebSocketServerAdapter.cs

@@ -5,20 +5,22 @@ using System.Threading;
 using System.Threading.Tasks;
 using MQTTnet.Core.Adapter;
 using MQTTnet.Core.Channel;
-using MQTTnet.Core.Diagnostics;
 using MQTTnet.Core.Serializer;
 using MQTTnet.Core.Server;
 using MQTTnet.Implementations;
+using Microsoft.Extensions.Logging;
 
 namespace MQTTnet.TestApp.AspNetCore2
 {
     public class MqttWebSocketServerAdapter : IMqttServerAdapter, IDisposable
     {
-        private readonly MqttNetTrace _trace;
+        private readonly ILogger<MqttWebSocketServerAdapter> _logger;
+        private readonly IMqttCommunicationAdapterFactory _mqttCommunicationAdapterFactory;
 
-        public MqttWebSocketServerAdapter(MqttNetTrace trace)
+        public MqttWebSocketServerAdapter(ILogger<MqttWebSocketServerAdapter> logger, IMqttCommunicationAdapterFactory mqttCommunicationAdapterFactory)
         {
-            _trace = trace ?? throw new ArgumentNullException(nameof(trace));
+            _logger = logger ?? throw new ArgumentNullException(nameof(logger));
+            _mqttCommunicationAdapterFactory = mqttCommunicationAdapterFactory ?? throw new ArgumentNullException(nameof(mqttCommunicationAdapterFactory));
         }
 
         public event EventHandler<MqttServerAdapterClientAcceptedEventArgs> ClientAccepted;
@@ -38,7 +40,7 @@ namespace MQTTnet.TestApp.AspNetCore2
             if (webSocket == null) throw new ArgumentNullException(nameof(webSocket));
 
             var channel = new MqttWebSocketServerChannel(webSocket);
-            var clientAdapter = new MqttChannelCommunicationAdapter(channel, new MqttPacketSerializer(), _trace);
+            var clientAdapter = _mqttCommunicationAdapterFactory.CreateServerMqttCommunicationAdapter(channel);
 
             var eventArgs = new MqttServerAdapterClientAcceptedEventArgs(clientAdapter);
             ClientAccepted?.Invoke(this, eventArgs);

Tests/MQTTnet.TestApp.AspNetCore2/Startup.cs

@@ -5,7 +5,6 @@ using Microsoft.AspNetCore.Hosting;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
 using MQTTnet.Core.Adapter;
-using MQTTnet.Core.Diagnostics;
 using MQTTnet.Core.Server;
 
 namespace MQTTnet.TestApp.AspNetCore2
@@ -14,25 +13,18 @@ namespace MQTTnet.TestApp.AspNetCore2
     {
         public void ConfigureServices(IServiceCollection services)
         {
+            services.AddMqttServer();
+            services.AddSingleton<MqttWebSocketServerAdapter>();
+            services.AddSingleton<IMqttServerAdapter, MqttWebSocketServerAdapter>();
         }
 
         public async void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
         {
             loggerFactory.AddConsole(LogLevel.Debug);
+            loggerFactory.AddDebug();
 
-            MqttNetTrace.TraceMessagePublished += (s, e) =>
-            {
-                Debug.WriteLine($">> [{e.TraceMessage.Timestamp}] [{e.TraceMessage.ThreadId}] [{e.TraceMessage.Source}] [{e.TraceMessage.Level}]: {e.TraceMessage.Message}");
-                if (e.TraceMessage.Exception != null)
-                {
-                    Debug.WriteLine(e.TraceMessage.Exception.Message);
-                }
-            };
-
-            var trace = new MqttNetTrace();
-            var adapter = new MqttWebSocketServerAdapter(trace);
-            var options = new MqttServerOptions();
-            var mqttServer = new MqttServer(options, new List<IMqttServerAdapter> { adapter }, new MqttNetTrace());
+            var adapter = app.ApplicationServices.GetService<MqttWebSocketServerAdapter>();
+            var mqttServer = app.ApplicationServices.GetService<IMqttServer>();
             await mqttServer.StartAsync();
             
             app.UseWebSockets();

Tests/MQTTnet.TestApp.NetCore/MQTTnet.TestApp.NetCore.csproj

@@ -3,10 +3,11 @@
   <PropertyGroup>
     <OutputType>Exe</OutputType>
     <DebugType>Full</DebugType>
-    <TargetFrameworks>netcoreapp2.0;net45</TargetFrameworks>
+    <TargetFrameworks>netcoreapp2.0;net451</TargetFrameworks>
   </PropertyGroup>
 
   <ItemGroup>
+    <PackageReference Include="Microsoft.Extensions.Logging" Version="1.1.2" />
     <PackageReference Include="Newtonsoft.Json" Version="10.0.3" />
   </ItemGroup>
 
@@ -15,4 +16,10 @@
     <ProjectReference Include="..\..\MQTTnet.Core\MQTTnet.Core.csproj" />
   </ItemGroup>
 
+  <ItemGroup>
+    <PackageReference Include="Microsoft.Extensions.Logging.Console">
+      <Version>1.1.2</Version>
+    </PackageReference>
+  </ItemGroup>
+
 </Project>

Tests/MQTTnet.TestApp.NetCore/ManagedClientTest.cs

@@ -2,10 +2,11 @@
 using System.Threading.Tasks;
 using MQTTnet.Core;
 using MQTTnet.Core.Client;
-using MQTTnet.Core.Diagnostics;
 using MQTTnet.Core.ManagedClient;
 using MQTTnet.Core.Packets;
 using MQTTnet.Core.Protocol;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Logging;
 
 namespace MQTTnet.TestApp.NetCore
 {
@@ -13,14 +14,14 @@ namespace MQTTnet.TestApp.NetCore
     {
         public static async Task RunAsync()
         {
-            MqttNetTrace.TraceMessagePublished += (s, e) =>
-            {
-                Console.WriteLine($">> [{e.TraceMessage.Timestamp:O}] [{e.TraceMessage.ThreadId}] [{e.TraceMessage.Source}] [{e.TraceMessage.Level}]: {e.TraceMessage.Message}");
-                if (e.TraceMessage.Exception != null)
-                {
-                    Console.WriteLine(e.TraceMessage.Exception);
-                }
-            };
+            var services = new ServiceCollection()
+                   .AddMqttClient()
+                   .AddLogging()
+                   .BuildServiceProvider();
+
+            services.GetService<ILoggerFactory>()
+                .AddConsole();
+
 
             var options = new ManagedMqttClientOptions
             {
@@ -35,7 +36,7 @@ namespace MQTTnet.TestApp.NetCore
 
             try
             {
-                var managedClient = new MqttClientFactory().CreateManagedMqttClient();
+                var managedClient = services.GetRequiredService<ManagedMqttClient>();
                 managedClient.ApplicationMessageReceived += (s, e) =>
                 {
                     Console.WriteLine(">> RECEIVED: " + e.ApplicationMessage.Topic);

Tests/MQTTnet.TestApp.NetCore/PerformanceTest.cs

@@ -1,4 +1,6 @@
-using MQTTnet.Core;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Logging;
+using MQTTnet.Core;
 using MQTTnet.Core.Client;
 using MQTTnet.Core.Packets;
 using MQTTnet.Core.Protocol;
@@ -17,33 +19,58 @@ namespace MQTTnet.TestApp.NetCore
     {
         public static async Task RunAsync()
         {
-            var server = Task.Factory.StartNew(RunServerAsync, TaskCreationOptions.LongRunning);
-            var client = Task.Factory.StartNew(() => RunClientAsync(2000, TimeSpan.FromMilliseconds(10)), TaskCreationOptions.LongRunning);
+            var services = new ServiceCollection()
+                .AddMqttServer(options => {
+
+                    options.ConnectionValidator = p =>
+                    {
+                        if (p.ClientId == "SpecialClient")
+                        {
+                            if (p.Username != "USER" || p.Password != "PASS")
+                            {
+                                return MqttConnectReturnCode.ConnectionRefusedBadUsernameOrPassword;
+                            }
+                        }
+
+                        return MqttConnectReturnCode.ConnectionAccepted;
+                    };
+
+                    options.DefaultCommunicationTimeout = TimeSpan.FromMinutes(10);
+                })
+                .AddMqttClient()
+                .AddLogging()
+                .BuildServiceProvider();
+
+            services.GetService<ILoggerFactory>()
+                .AddConsole(minLevel: LogLevel.Warning, includeScopes: true);
+            
+            Console.WriteLine("Press 'c' for concurrent sends. Otherwise in one batch.");
+            var concurrent = Console.ReadKey(intercept: true).KeyChar == 'c';
+
+            var server = Task.Factory.StartNew(() => RunServerAsync(services), TaskCreationOptions.LongRunning);
+            var client = Task.Factory.StartNew(() => RunClientAsync(2000, TimeSpan.FromMilliseconds(10), services, concurrent), TaskCreationOptions.LongRunning);
 
             await Task.WhenAll(server, client).ConfigureAwait(false);
         }
 
-        private static Task RunClientsAsync(int msgChunkSize, TimeSpan interval)
+        private static Task RunClientsAsync(int msgChunkSize, TimeSpan interval, IServiceProvider serviceProvider, bool concurrent)
         {
-            return Task.WhenAll(Enumerable.Range(0, 3).Select(i => Task.Run(() => RunClientAsync(msgChunkSize, interval))));
+            return Task.WhenAll(Enumerable.Range(0, 3).Select(i => Task.Run(() => RunClientAsync(msgChunkSize, interval, serviceProvider, concurrent))));
         }
 
-        private static async Task RunClientAsync(int msgChunkSize, TimeSpan interval)
+        private static async Task RunClientAsync(int msgChunkSize, TimeSpan interval, IServiceProvider serviceProvider, bool concurrent)
         {
             try
             {
                 var options = new MqttClientTcpOptions
                 {
                     Server = "localhost",
-                    ClientId = "XYZ",
+                    ClientId = "Client1",
                     CleanSession = true,
                     DefaultCommunicationTimeout = TimeSpan.FromMinutes(10)
                 };
 
-                var client = new MqttClientFactory().CreateMqttClient();
-                client.ApplicationMessageReceived += (s, e) =>
-                {
-                };
+                var client = serviceProvider.GetRequiredService<IMqttClient>();
 
                 client.Connected += async (s, e) =>
                 {
@@ -113,8 +140,7 @@ namespace MQTTnet.TestApp.NetCore
                         .Select(i => CreateMessage())
                         .ToList();
 
-                    Console.WriteLine("Press 'c' for concurrent sends. Otherwise in one batch.");
-                    if (Console.ReadKey().KeyChar == 'c')
+                    if (concurrent)
                     {
                         //send concurrent (test for raceconditions)
                         var sendTasks = msgs
@@ -165,28 +191,11 @@ namespace MQTTnet.TestApp.NetCore
             return Task.Run(() => client.PublishAsync(applicationMessage));
         }
 
-        private static async Task RunServerAsync()
+        private static async Task RunServerAsync(IServiceProvider serviceProvider)
         {
             try
             {
-                var options = new MqttServerOptions
-                {
-                    ConnectionValidator = p =>
-                    {
-                        if (p.ClientId == "SpecialClient")
-                        {
-                            if (p.Username != "USER" || p.Password != "PASS")
-                            {
-                                return MqttConnectReturnCode.ConnectionRefusedBadUsernameOrPassword;
-                            }
-                        }
-
-                        return MqttConnectReturnCode.ConnectionAccepted;
-                    },
-                    DefaultCommunicationTimeout = TimeSpan.FromMinutes(10)
-                };
-
-                var mqttServer = new MqttServerFactory().CreateMqttServer(options);
+                var mqttServer = serviceProvider.GetRequiredService<IMqttServer>();
                 var msgs = 0;
                 var stopwatch = Stopwatch.StartNew();
                 mqttServer.ApplicationMessageReceived += (sender, args) =>

Tests/MQTTnet.TestApp.NetCore/Program.cs

@@ -1,6 +1,5 @@
 using MQTTnet.Core;
 using MQTTnet.Core.Client;
-using MQTTnet.Core.Diagnostics;
 using MQTTnet.Core.Packets;
 using MQTTnet.Core.Protocol;
 using MQTTnet.Core.Server;
@@ -12,6 +11,8 @@ using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
 using Newtonsoft.Json;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Logging;
 
 namespace MQTTnet.TestApp.NetCore
 {
@@ -24,7 +25,7 @@ namespace MQTTnet.TestApp.NetCore
             Console.WriteLine("2 = Start server");
             Console.WriteLine("3 = Start performance test");
             Console.WriteLine("4 = Start managed client");
-
+                        
             var pressedKey = Console.ReadKey(true);
             if (pressedKey.KeyChar == '1')
             {
@@ -48,17 +49,16 @@ namespace MQTTnet.TestApp.NetCore
 
         private static async Task RunClientAsync()
         {
-            MqttNetTrace.TraceMessagePublished += (s, e) =>
-            {
-                Console.WriteLine($">> [{e.TraceMessage.Timestamp:O}] [{e.TraceMessage.ThreadId}] [{e.TraceMessage.Source}] [{e.TraceMessage.Level}]: {e.TraceMessage.Message}");
-                if (e.TraceMessage.Exception != null)
-                {
-                    Console.WriteLine(e.TraceMessage.Exception);
-                }
-            };
-
             try
             {
+                var services = new ServiceCollection()
+                    .AddMqttServer()
+                    .AddLogging()
+                    .BuildServiceProvider();
+
+                services.GetService<ILoggerFactory>()
+                    .AddConsole();
+
                 var options = new MqttClientWebSocketOptions
                 {
                     Uri = "localhost",
@@ -66,7 +66,7 @@ namespace MQTTnet.TestApp.NetCore
                     CleanSession = true
                 };
 
-                var client = new MqttClientFactory().CreateMqttClient();
+                var client = services.GetRequiredService<IMqttClient>();
                 client.ApplicationMessageReceived += (s, e) =>
                 {
                     Console.WriteLine("### RECEIVED APPLICATION MESSAGE ###");
@@ -139,7 +139,12 @@ namespace MQTTnet.TestApp.NetCore
         private static async void WikiCode()
         {
             {
-                var client = new MqttClientFactory().CreateMqttClient(new CustomTraceHandler("Client 1"));
+                var serviceProvider = new ServiceCollection()
+                    .AddMqttServer()
+                    .AddLogging()
+                    .BuildServiceProvider();
+
+                var client = serviceProvider.GetRequiredService<IMqttClient>();
 
                 var message = new MqttApplicationMessageBuilder()
                     .WithTopic("MyTopic")
@@ -159,28 +164,6 @@ namespace MQTTnet.TestApp.NetCore
         }
     }
 
-    public class CustomTraceHandler : IMqttNetTraceHandler
-    {
-        private readonly string _clientId;
-
-        public CustomTraceHandler(string clientId)
-        {
-            _clientId = clientId;
-        }
-
-        public bool IsEnabled { get; } = true;
-
-        public void HandleTraceMessage(MqttNetTraceMessage traceMessage)
-        {
-            // Client ID is added to the trace message.
-            Console.WriteLine($">> [{_clientId}] [{traceMessage.Timestamp:O}] [{traceMessage.ThreadId}] [{traceMessage.Source}] [{traceMessage.Level}]: {traceMessage.Message}");
-            if (traceMessage.Exception != null)
-            {
-                Console.WriteLine(traceMessage.Exception);
-            }
-        }
-    }
-
     public class RetainedMessageHandler : IMqttServerStorage
     {
         private const string Filename = "C:\\MQTT\\RetainedMessages.json";

Tests/MQTTnet.TestApp.NetCore/ServerTest.cs

@@ -1,9 +1,10 @@
 using System;
 using System.Text;
 using System.Threading.Tasks;
-using MQTTnet.Core.Diagnostics;
 using MQTTnet.Core.Protocol;
 using MQTTnet.Core.Server;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Logging;
 
 namespace MQTTnet.TestApp.NetCore
 {
@@ -11,20 +12,15 @@ namespace MQTTnet.TestApp.NetCore
     {
         public static Task RunAsync()
         {
-            MqttNetTrace.TraceMessagePublished += (s, e) =>
-            {
-                Console.WriteLine($">> [{e.TraceMessage.Timestamp:O}] [{e.TraceMessage.ThreadId}] [{e.TraceMessage.Source}] [{e.TraceMessage.Level}]: {e.TraceMessage.Message}");
-                if (e.TraceMessage.Exception != null)
-                {
-                    Console.WriteLine(e.TraceMessage.Exception);
-                }
-            };
-
             try
             {
-                var options = new MqttServerOptions
+                var services = new ServiceCollection()
+                    .AddMqttServer()
+                    .AddLogging();
+
+                services.Configure<MqttServerOptions>(options =>
                 {
-                    ConnectionValidator = p =>
+                    options.ConnectionValidator = p =>
                     {
                         if (p.ClientId == "SpecialClient")
                         {
@@ -35,22 +31,24 @@ namespace MQTTnet.TestApp.NetCore
                         }
 
                         return MqttConnectReturnCode.ConnectionAccepted;
-                    }
-                };
+                    };
 
-                options.Storage = new RetainedMessageHandler();
+                    options.Storage = new RetainedMessageHandler();
 
-                options.ApplicationMessageInterceptor = message =>
-                {
-                    if (MqttTopicFilterComparer.IsMatch(message.Topic, "/myTopic/WithTimestamp/#"))
+                    options.ApplicationMessageInterceptor = message =>
                     {
-                        // Replace the payload with the timestamp. But also extending a JSON 
-                        // based payload with the timestamp is a suitable use case.
-                        message.Payload = Encoding.UTF8.GetBytes(DateTime.Now.ToString("O"));
-                    }
+                        if (MqttTopicFilterComparer.IsMatch(message.Topic, "/myTopic/WithTimestamp/#"))
+                        {
+                            // Replace the payload with the timestamp. But also extending a JSON 
+                            // based payload with the timestamp is a suitable use case.
+                            message.Payload = Encoding.UTF8.GetBytes(DateTime.Now.ToString("O"));
+                        }
 
-                    return message;
-                };
+                        return message;
+                    };
+                });
+
+                var serviceProvider = services.BuildServiceProvider();
 
                 //var certificate = new X509Certificate(@"C:\certs\test\test.cer", "");
                 //options.TlsEndpointOptions.Certificate = certificate.Export(X509ContentType.Cert);
@@ -58,7 +56,7 @@ namespace MQTTnet.TestApp.NetCore
                 //options.DefaultEndpointOptions.IsEnabled = true;
                 //options.TlsEndpointOptions.IsEnabled = false;
 
-                var mqttServer = new MqttServerFactory().CreateMqttServer(options);
+                var mqttServer = serviceProvider.GetRequiredService<IMqttServer>();
                 mqttServer.ClientDisconnected += (s, e) =>
                 {
                     Console.Write("Client disconnected event fired.");